As good as it gets. The first carbonated drink was Schweppes Tonic which was developed so that people could drink quinine as medicine in spite of its bitter taste. You can formulate bitter soft drinks without quinine but you may not be able to call them tonics depending on local legislation. Without quinine you also loss the slight blue phosphorescence of tonic water.
Auxiliary verb + do In British English it is common to use do as a substitute verb after an auxiliary verb. Americans do not normally use do after an auxiliary verb. There is no formal reason for it. It's just another idiosyncrasy that separates the British and American forms of the language we call English.
A Sub or Substitute.
The British call a flashlight a torch.
you can not substitute me. The director Substituted lead actor.
A good substitute for hominy in recipes is corn kernels or cornmeal. These alternatives can provide a similar texture and flavor to dishes that call for hominy.
A good substitute for hondashi in recipes is bonito flakes or dashi powder.
A suitable substitute for potato flakes in recipes is instant mashed potatoes.
What Americans call pants, the British would call trousers.
You might call it ''ANARCHY".
Agar agar is a suitable vegetarian gelatin substitute for recipes that call for gelatin. It is derived from seaweed and can be used in a similar way to gelatin in recipes.
....a can.